Strain gauge measurements and analysis of structures

Use of strain gauges may tell you whether your structure is exposed to loads that are so critical that failure is bound to occur. Let us assist you in strain gauge measuring as well as gaining the optimal knowledge from the measurements.

The advantage of strain gauge measuring

Strain gauge measuring provides you with certainty about the actual stress in the structure. This stress can be compared to the calculations upon which the structural design is based. Thus, you are certain that the calculations are correct.

If this is not the case, we will assist you in assessing whether the correct calculation preconditions have been applied, or whether you have to revise your calculation model. Often many factors and preconditions are hard to design in the calculations.

You can apply the results from strain gauge measuring with fracture mechanics analyses, where strain gauge measuring forms the basis of the stress spectrum you use for assessment of crack growth of defects in welds.

What is a strain gauge, and how to use it?

The size of structures have grown over time and have become more complicated to analyse. The technological development has provided the opportunity to analyse stresses in structures by advanced finite element software. Despite the advanced analysis methods, the results seldom paint a correct picture.

The most common type of strain gauge consists, in principle, of a resistance wire fixed to the structure. When you load it, the resistance changes, and by measuring this change you get an impression of the structure’s state of strain and stress.

Most often strain gauges are glued to a ground area. From the strain gauges, you then draw wires to a data logger collecting data, and subsequently you store the data in a computer. The strain gauges monitor and log the actual strains in the surface in the selected critical positions. Based on the measured strains, you may calculate the stresses where the strain gauges have been fitted.

We measure strain on:

Bridges

Offshore structures

Wind turbines

Cranes

Machines and machine components, also rotating parts and bolts

Pressure equipment

Concrete structures.

By monitoring in positions that are hard-to-get-to, such as offshore wind turbines, FORCE Technology provides the opportunity of remotely monitoring of the measurements. This is possible if you have an installed internet connection in the monitoring position or, alternatively, by use of the mobile network.

This way you can monitor the actual strains and stresses, or download saved data for analysis on a regular basis.

You can use the results to continuously monitoring the state of the structure on which the strain gauges are fitted, and thus be on top of the situation to prevent a critical failure.

Contact us if you need to determine the loads on your structure or wish to hear more about how we may help you.